Genetics - Exam 2 practice qs - Kessler

C

.In the following trihybrid cross, what is the probability of genotype PPYyrr occurring in the offspring? PpYyRr x PPyyR A. 1/4 B. 1/8 C. 1/16 D. 1/24 E. 1/32

C

5'CAGGAGTTAACGAGATGGGGATCCCAAACGTAGCGTAA-3' 3'GTCCTCAATTGCTCTACCCCTAGGGTTTGCATCGCATT-5' The above sequence is a short gene in E. coli that makes a polypeptide. Assume the entire region is transcribed. What would be the RNA sequence produced after transcription? A.3'CAGGAGUUAACGAGAUGGGGAUCCCAAACGUAGCGUAA-5' B.3'GUCCUCAAUUGCUCUACCCCUAGGGUUUGCAUCGCAUU-5' C.5'CAGGAGUUAACGAGAUGGGGAUCCCAAACGUAGCGUAA-3' D.5'GUCCUCAAUUGCUCUACCCCUAGGGUUUGCAUCGCAUU-3'

C

A cross between two individuals with different phenotypes that resulted in approximately 50% of each type of offspring would indicate the cross was ________. A) true breeding dominant with true breeding recessive B) heterozygous crossed with heterozygous C) heterozygous crossed with a homozygous recessive D) homozygous dominant crossed with heterozygous E) true breeding dominant with heterozygous

C

A recessive gene for red-green color blindness is located on the X chromosome in humans. A woman with normal vision (her father is color blind) is expecting a baby boy with a color-blind male. What is the likelihood that this couple's baby boy will be color blind? A) 25% B) 0% C) 50% D) 100%

D

Achondroplasia is a form of human dwarfism. If two individuals with achondroplasia have children with the following ratio, 2 dwarf to 1 wild type, what means of inheritance explains this phenotypic outcome? A) simple dominance B) simple recessive C) dominant lethal D) recessive lethal E) epistasis

C

An aminoacyl tRNA synthase Valine is mutated so that it now attaches the amino acid glycine to the tRNA Valine instead of valine. What will happen at translation? A. There will be glycine at all valine positions and valines at all glycine positions. B. There will be valines at all glycine positions and glycines at all valine positions. C. There will be glycines at all glycine positions and at all valine positions. D. There will be valines at all glycine positions and at all valine positions. E. There will be no translation

B

An mRNA that is being produced comes off of the ________. A) coding strand in both bacteria and eukaryotes B) template strand in both bacteria and eukaryotes C) coding strand in bacteria and the template strand in eukaryotes D) template strand in bacteria and the coding strand in eukaryotes E) coding or template strand in both bacteria and eukaryotes depending upon the species

C

Assuming complete dominance, what phenotypic ratio would you expect from a monohybrid self-cross? A) 1:1 B) 2:1 C) 3:1 D) 3:2

B

Assuming no crossing over between the gene in question and the centromere, when do alleles segregate during meiosis? A) prophase I B) anaphase I C) prophase II D) anaphase II

D

During bacterial translation initiation, the mRNA_. A. binds to the large subunit B. is oriented so that the AUG start codon is in the A site C. only binds f-Met tRNA after the entire ribosome has been assembled D. is oriented on the small subunit by its Shine-Dalgarno sequence through base pairing with an rRNA E. requires ATP hydrolysis for binding to the ribosomal subunit

B

Female 12 is twenty years old and does not want to get a genetic test to determine if she is a carrier for Huntington's disease. She is currently pregnant with a child by another 20-year-old who has no history of Huntington's disease in his family. Assuming the father of the child is not a Huntington's carrier, what is the likelihood that their child will have Huntington's disease (dominant)? A.0% B.25% C.50% D.75% E.100%

B

For a monohybrid cross of Yy plants, what is the probabilities of the offspring genotypes? A. ½ YY, ½ Yy, ½ yy B. ¼ YY, ½ Yy, ¼ yy C. ¼ YY, ¼ Yy, ¼ yy D. ¼ YY, ½ Yy, ½ yy

C

How could you figure out the genotype of this plant? DD or Dd? A.Cross it to a homozygous dominant plant. B.Cross it to a plant with the dominant trait but a similarly unknown genotype. C.Cross it to a plant with the recessive trait D.Cross it to a heterozygous dominant plant. E.It cannot be determined

B

How many degrees of freedom are there in a dihybrid cross? n=4 A. 2 B. 3 C. 4 D. 9 E. 16

D

If complete linkage occurs, what would you expect to see? A) a 9:3:3:1 ratio in the F2 generation B) a 1:1:1:1 ratio in the test cross C) only recombinant phenotypes in the F2 of the appropriate test cross D) only parental phenotypes in the F2 of the appropriate test cross E) four different phenotypes in the offspring in the F2 of the appropriate test cross

C

In Drosophila, white eyes are due to an X-linked recessive allele (Xw), What genetic cross could result in white-eyed female Drosophila? A. no possible cross B. white-eyed females with red-eyed males C. heterozygous red-eyed females with white-eyed males D. heterozygous red-eyed females with red- eyed males

E

In mice, there is a set of multiple alleles of a gene for coat color. Four of those alleles are as follows: C = full color (wild type) cch= chinchilla cd= dilution c= albino. Given that the gene locus is not sex-linked and that each allele is dominant to those lower in the list, give the phenotypic ratios expected from the following cross: hinchilla (heterozygous for albino) ×albino A) 1 dilution : 1 chinchilla : 1 albino B) 1 full color : 1 chinchilla : 1 albino C) 2 chinchilla : 1 albino D) 1 chinchilla : 2 albino E) 1 chinchilla :1 albino

B

In mice, there is a set of multiple alleles of a gene for coat color. Four of those alleles are as follows: C = full color (wild type) cch= chinchilla cd= dilution c= albino. Given that the gene locus is not sex-linked and that each allele is dominant to those lower in the list, give the phenotypic ratios expected from the following cross: wild (heterozygous for dilution) ×chinchilla (heterozygous for albino) A) 1 chinchilla : 2 dilution : 1 albino B) 2 full color : 1 chinchilla : 1 dilution C) 1 full color : 1 chinchilla : 1 dilution : 1 albino D) 2 full color : 2 chinchilla : 1 dilution E) 1 full color : 1 chinchilla : 2 dilution : 1 albino

B

In which of the following human genetic conditions would the person be missing a chromosome? A) Down's syndrome B) Turner syndrome C) Jacob syndrome D) Klinefelter syndrome

E

Jim is a man who carries an X-linked gene. Assuming normal meiosis and random combination of gametes, if Jim has children, who would he pass this gene to A) all of his sons B) half of his daughters C) half of his sons D) all of his children E) all of his daughters

C

Meiosis in humans reducesploidy from 2n to n in gametes. When does this reduction in ploidy take place? A. Prophase I of meiosis B. Prophase II of meiosis C. Anaphase I of meiosis D. Anaphase II of meiosis E. Telophase II of meiosis

D

Mendel crossed two pea plants with round seeds. All seeds of the offspring were round. He then crossed a plant with round seeds to a plant with wrinkled seeds and all offspring had wrinkled seeds. Which of the following is true? A) the trait does not breed true B) round is dominant C) a mutation occurred D) wrinkled is dominant

D

Of the following statements, which accurately describes segregation? A) Genes lie on chromosomes B) During gamete formation, segregating pairs of unit factors assort independently of each other. C) Chromosomes can swap information during meiosis. D) During gamete formation, allele pairs are separated to form haploid gametes. E) During gamete formation, segregating pairs of unit factors assort independently of each other.

D

Polydactyly is a genetic condition, caused by a dominant allele, where an individual has extra digits (fingers and/or toes). Say a man with six fingers on each hand and six toes on each foot marries a woman with a normal number of digits. The couple has a son with normal hands and feet, but the couple's second child has extra digits. What is the probability that their next child will have polydactyly? A) 1/32 B) 1/8 C) 7/16 D) 1/2 E) 3/4

C

Reading the RNA sequences in a 5ʹ to 3ʹ direction, a base at the first position of an anticodon on the tRNA would pair with a base at the ________ position of the mRNA. A. First B. Second C. Third D. Fourth

D

Say a cross is made between plants with genotypes AaBb and aabb, and all the offspring produced are either AaBb or aabb. These results are consistent with _______. A) incomplete dominance B) alternation of generations C) hemizygosity D) complete linkage E) codominance

False

Sex-limited inheritance is the same as sex-linked inheritance True or False

A

The autosomal gene for brachydactyly(short fingers) is dominant to normal finger length. Assume that a female with brachydactyly in the heterozygous condition is married to a man with normal fingers. What is the probability that their first child will be a boy with brachydactyly? A) 1/4 B) 1/2 C) 1/8 D) 3/4 E) 2/3

B

The coding strand of a portion of a gene reads 5ʹ ACTGGTTCA. What will be the sequence of the resulting transcript for this portion? A.5ʹ UGACCAAGU B.5ʹ ACUGGUUCA C.5ʹ UGAACCAGU D.5ʹ ACUUGGUCA

D

The gene that is responsible for determining "maleness" is contained on a small part of the human Y chromosome. What is the name of this gene? A) Xist B) Bro C) Dax D) SRY

C

The presence of more than two alternative forms of a given gene would be called A) incomplete dominance B) alternation of generations C) multiple alleles D) codominance

A

The primary structure of a protein is determined by ________. A) the sequence of amino acids B) hydrogen bonds formed between the components of the peptide linkage C) a series of helical domains D) pleated sheets E) covalent bonds formed between fibroin residue

E

Tightly curled hair is a phenotype caused by a dominant gene in humans. Say a heterozygous curly-haired person marries a person with straight hair, what percentage of their offspring would be expected to have straight hair? A) 75% B) 25% C) 100% D) Impossible to tell from the information given E) 50%

D

Two forms of hemophilia are determined by genes on the X chromosome in humans. Assume that a phenotypically normal woman whose father had hemophilia is married to a man without hemophilia. What is the probability that their first son will have hemophilia? A) 0 B) 1/3 C) 1/4 D) 1/2 E) 100%

D

What is the 5ʹ→ 3ʹ sequence on the anticodon of the methionine (Met) tRNA? A. AUG B. GUA C. UAC D. CAU

D

What is the ultimate source of new alleles? A. Transcription B. Crossing over C. Independent assortment D. Mutations E. Vertical gene transfer

A

What level of protein structure is most immediately coded for in DNA? A. primary B. secondary C. tertiary D. quaternary E. There is no difference between the four answer

C

What meiotic process, relative to the number of chromosomes of a given species, accounts for a significant amount of genetic variation in gametes? A) formation of the meiotic spindle during chromosome segregation B) bivalent formation C) independent assortment of chromosomes D) pairing of homologous chromosomes

B

What term is normally used when two genes fail to assort independently? A) discontinuous inheritance B) linkage C) dominance and/or recessiveness D) Mendelian inheritance

D

Which of the following crosses would result in a phenotypic ratio of 1:1:1:1? A) AABB × aabb B) AAbb × aaBB C) AaBb × AaBb D) AaBb × aabb

D

Which of the following sequences of mRNA codes for five amino acids, with the correct punctuation and polarity? A. 3'-AUGUGCCCUCGAUUUUGACGG -5' B. 3'-AAUACUGCGGCUGUACCGGAG -5' C. 5'-AUGCCCUGGUGAUAAUCC -3' D. 5'-CUGAUGCGUGAAAGAUAUUAG -3'

A

With incomplete dominance, a likely ratio resulting from a monohybrid cross would be A) 1:2:1 B) 1:2 C) 1:2:2:4 D) 9:3:3:1 E) 3:1

E

With which of the following would hemizygosity most likely be associated? A) codominance B) incomplete dominance C) autosomal dominance D) sex-limited inheritance E) X-linked inheritance

B

You have identified a plant in your garden with a new, blue petal color. You want to determine if this phenotype is dominant or recessive. Which of the following crosses would give you the answer? A) crossing the plant to a plant of the same type of any color B) crossing the plant to one you know has the recessive trait C) crossing the new plant to one you know has the dominant trait D) sequencing the DNA for the trait

C

¼ YY, ½ Yy, ¼ yy¼ RR, ½ Rr, ¼ rr What is the probability of genotype yyRr occurring in the F2 generation? A. 1/2 B. 1/4 C. 1/8 D. 1/16